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Main Relay (Computer/Fuel System): Description and Operation

PURPOSE
The Electronic Fuel Injection Main Relay serves as a source of battery power for several components including the Circuit Opening Relay, (which powers the Fuel Pump), and the Engine Control Module (ECM).

OPERATION
The main relay is energized by a signal from the Ignition Switch. It then supplies battery current from the EFI fuse to the ECM and other components.